Manual drive for hydraulic servomotors



Oct. 28, 1952 s. A. JACQUES 2,615,429

MANUAL DRIVE FOR HYDRAULIC SERVOMOTORS Filed Nov. 27, 1950 5Sheets-Sheet l I N VEN TOR.

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Oct. 28, 1952 s, A. JACQUES 2,615,429

MANUAL DRIVE FOR HYDRAULIC SERVOMOTORS Filed Nov. 27, 1950 5 SheetsSheet2 Oct. 28, 1952 5. A. JACQUES 2,615,429

MANUAL DRIVE FOR HYDRAULIC SERVOMOTQRS Filed Nov. 27, 1950 5Sheets-Sheet 3 Oct. 28, 1952 5 JACQUES 2,615,429

A MANUAL DRIVE FOR HYDRAULIC SERVOMOTORS Filed Nov. 27, 1950 5Sheets-Sheet 4 Jay 7 pn'miii 37 1- 5/ 5,2 f0 3 IN V EN TOR.

Oct. 28, 1952 s. A. JACQUES MANUAL DRIVE FOR HYDRAULIC SERVOMOTORS 5Sheets-Sheet 5 Filed Nov. 27, 1950 INVENTOR an] yCLJac ues W CZiZarzzgs' Patented Oct. 28, 1952 MANUAL DRIVE FOR HYDRAULIC SERVOMOTORSStanley A. Jacques, Chicago, 111., assignor to Askania RegulatorCompany, Chicago, 111., a corporation of Illinois Application November27, 1950, Serial No. 197,796

2 Claims. (Cl. 121-38) The present invention relates to hydrauliccylinder and piston assemblies of the kind constituting the output orpower unit of hydraulic systems such as power amplifiers or relays.

Such units, in addition to being operable hydraulically under control ofsome'apparatus that acts to regulate delivery of operating fluid to theunit to move a load, in many instances are provided with auxiliarymechanical systems that permit manual movement of the load and thepiston that is connected to drive it. Manual movement of a hydraulicpower unit piston that is blocked from its regulator requires bleedingof the cylinder ends to prevent fluid lock, and conveniently suchbleeding is accomplished by a bypass path that may be established tointerconnect the cylinder ends for manual piston movement, or blockedfor normal hydraulic piston actuation. Conversion of a hydraulic powersystem between conditions for hydraulic and manual operation requiresoperation of three valves, two to block or clear communication of thecylinder ends with the hydraulic system output lines, and one to blockor clear the bleeder by-pass. A mechanical drive system for a heavilyloaded piston must be designed to exert a large force, and breakingmeans are necessary to maintain the load and piston in selected.positions. Also the mechanical system almost necessarily isdisconnectible from the piston system for normal hydraulic operation ofthe latter;

For so-called purging or cleaning out a hydraulic power system,sometimes it is required that provision be made to interconnect the twocylinder lines at or close to the power unit, blocking such lines fromcommunication with the cylinder so that a closed circuit between theregulator and power unit is established through which fluid can becirculated. I

A primary object of the invention is the provision in a piston andcylinder power unit for a hydraulic relay system, of a novel arrangementof a mechanical system that is manually movable for moving the pistonand a load connected to it.

Another primary object is the provision of a novel arrangement forconnecting and disconnecting such a mechanical system to and from theoperating assembly of a piston and cylinder power unit.

. Another object is the provision of a novel meehanical piston-drivingsystem that cannot be driven by a piston with which it isinterconnected.

An additionalobject of great importance, is the novel combination of amechanical piston-driving system that is connectible and disconnectiblesary to convert the unit between conditions for.

mechanical and hydraulic drive, in such operative association that themechanism movements required to establish or disestablish the mechanicaldrive system respectively actuate the valve to convert the power unitbetween hydraulic conditions for mechanical and hydraulic piston drive.

Another object is the provision of a novel, unitary assembly of acylinder, piston, by-pass and valve means for connecting the cylinderends to hydraulic lines and blocking the by-pass, or blocking thecylinder ends from hydraulic lines and establishing the by-pass.

An additional object is the provision of a novei arrangement permittingestablishment, for purging, of a cross connection between hydraulicsystem output lines and blocking'such lines from Fig. 2 is a partial topplan and partial horizontal section, as indicated by line 2-2 of Fig. 1.

Fig. 3 is an end elevation.

Fig. 4 is an elevation of the side of the unit opposite that seen inFig. l.

' Fig. 5 is a section on line 55 of Fig. 1.

Fig. 6 is a longitudinal vertical section on line' 6-6 of Fig. 2.

Fig. 7 is a detail horizontal section'through the valve chamber, showingthe valve incondition establishing a by-pass between the cylinder ends,

and blocking the cylinder ends from communication with input openings towhich hydraulic controlsystem lines are to be connected.

Fig. 8 is a view similar to Fig. 7,,but showing. the valve body in acondition blockingjtheiby pass and connecting thecylinder ends with the.

input openings.

Fig. 9 is a section on line 99 of Fig. 8. Fig. 10 is a side elevation ofa power unit having the same general arrangement as that shown, in Figs.1 to 9, but provided with a special form. of valve providing forinterconnection of the in-.

put openings, blocking of the by-passand blocking communication betweenthe cylinder ends and-- input openings 'f orpurging hydraulic lines connected with the input openings.

Fig. 11 is an enlarged fragmentary elevation showing an auxiliary valveoperator that is used to establish the purging condition of the valve.

Figs. 12, 13, and 14 are similar fragmentary vertical median sectionsthrough the valve assembly, showing the valve body respectively inpositions for normal hydraulic piston operation, mechanical pistonoperation, and purging of hydraulic lines connected to the unit inputopenmgs.

Figs. 15 and 16 are fragmentary horizontal sections showing the valve inpurging and normal operation positions.

Fig. 17 is a fragmentary horizontal section showing a device forindexing the valve in its purging position.

Describing the drawings in detail, and first referring to Figs. 5 and 6,a hydraulic power unit comprises a piston l5 that is reciprocable in acylinder to drive, through a piston rod 17 and crank iii, an outputshaft IS. The power unit includes a housing structure that includes abarrel portion 20 enclosing cylinder I 6, and a crankcase portion 2! inopposite walls of which shaft I9 is supported by bearings 22. Shaft l9projects from crankcase 2| at both sides of the latter, and at one ofits ends carries an output device, shown in Figs. 1 and 2 as a crank 23.

.In accordance with the invention the second end of shaft I9 has securedto it a worm gear 24 that acts as the driven element of a mechanicalpiston-driving system that may be made effective and actuated to rotateshaft it, for moving a load connected to the output crank 23. Themechanical system for rotating worm gear 24 includes a worm 25 mountedon a support shaft 26 that is pivoted to the housing structure forswinging between two positions, one of which is shown in Figs. 1, 2, and4, and wherein the worm 25 is meshed with gear 24, while in the otherposition, shown in Fig. 10, and indicated in dotted lines in Fig. 4, theworm is disengaged from the gear. When the worm is meshed with gear 24,its rotation drives shaft l9, and additionally its engagement with thegear serves as a positive stop against rotation of shaft 19 by a load orby the piston.

Shaft 26 is shown as rotatable and secured to worm 25, thereby itselfserving as a drive shaft as well as a support shaft for the worm. Theshaft is rotatably mounted in a frame 27 that has an upper bearing part28 and a lower hearing part 29 that is secured to a pivot shaft 30rotatably mounted in the housing structure. Shaft 36 also functions as avalve body, as will be explained. A portion of frame 21' carries adetent plunger 3! that cooperates with suitably located holes 32 in anindexing plate 33 that is fixed to the housing structure. One hole 32 islocated to maintain shaft 26 in an angular position of proper meshingengagement of worm 25 with gear 24, and, as will appear, maintain thevalve body shaft 38 in an angular position for mechanical piston drive.The other hole 32 is located to latch shaft 26 in an angular positionwith worm 25 disengaged from gear 26, and wherein shaft 30 is angularlypositioned for hydraulic piston drive.

The hydraulic system of the unit comprises a pair of external inputopenings for connection to the two output lines of a hydraulicpistonactuating system that operates to selectively connect such linesto pressure fluid supply and exhaust. These input openings 35 form theends of a pair of cylinder passages that have input with astraight-through passage ii located to connect ports 39 when the shaftis in the angular indexed position meshing worm 25 with gear 24, as seenin Figs. 6 and 7. Additionally, the

shaft is provided with longitudinal flats 42 providing passages thatinterconnect the ports 39, 40 that are on the same sides of bore 38, asseen in Figs. '7 and 9, when shaft Si! is in its second indexedposition. By this arrangement, when shaft 26 is latched in-its positionmeshing worm 25 with gear 24 for mechanical piston drive, as byfahandwheel 65 secured to shaft 26, the opposite ends of cylinder It areconnected together through a by-pass comprising the two passage reaches31 and valve body passage 4!, and the passages provided by flats 42 areangularly displaced from registration with ports 39, 40, so that thecylinder reaches 31 are cut oif from the input reaches 36 and fromsystem lines connected with the input openings 35. In this condition,

rotation of handwheel 45 rotates shaft 26 and the worm attached to thelatter. Since worm 25 is meshed with worm gear 24, and the latter,through main shaft 19, crank 18 and link I! is coupled to piston iii,the latter is driven in cylinder 16, which is freely permitted bypassage of fluid through the by pass between the cylinder ends describedimmediately above. When valve body shaft 38 is in its second position,wherein body passage M is angularly displaced from registration withports 39 and the passages provided by flats 42 connect correspondingpairs of ports 39, 4B, shaft 2%} is in an angular position wherein worm25 is disengaged from gear 24.

It will be noted that the arrangement described above is well suited toproduction as a unitary assembly wherein all necessary passage lines andthe valve chamber are formed as bores in a single main casting ofconfiguration providing for passage and valve housing, as by anenlargement 46 along one side of the cylinder containing a passage reach3'. and a transverse enlargement 41 containing valve bore 38.

The power unit of Figs. 10 to 16 is the same as that described aboveexcept the valve body and its connection to shaft 26 are modified toprovide a third hydraulic condition for line purging, by blocking bothcylinder ends from the input passage reaches 36 and interconnectingthose passage reaches at the valve. To this end the valve body shaft,designated 50, is again provided with a through passage 5! angularlypositioned to interconnect ports 39 when worm 25 is meshed with gear 24.Shaft 50 also is provided with passage-forming grooves extended alongopposite sides of the shaft and positioned circumferentially thereof tointerconnect corresponding pairs of ports 39, 49 when the shaft is inits second indexed position. One groove, shown as 52, is only ofsufficient length to extend between the pair of ports 39, 58 that itinterconnects. The other groove 53 extends axially of the shaft pastport 39 and to have a portion spaced circumferentially of shaft 50 fromthe part of groove 52 that registers with its associated port 40.Located to register with the two ports 40 are ways 54 that communicatewith groove 53. These Ways are so arranged in shaft 50 as to providecommunication of both ports 4!] with groove 53 in an angular position ofshaft 50 that is reached by rotating the shaft a preselected angulardistance beyond its second indexed position and in the same direction asits rotation from the position of meshing of worm 25 with gear 24.

Purging usually is an operation that is performed only occasionally. Asseen from Fig. 10, the second indexed position of worm-support assemblypreferably is alongside the cylinder barrel 20. From theseconsiderations it is regarded as preferable to releasably connect thesupport shaft, designated 26 in Figs. and 11, to valve shaft 50, so thatthe latter may bereleased and rotated to its third position, whilesupport shaft 26 may remain in either of its indexed positions.Referring to Figs. 10 and 11, valve shaft 50 extends through a bearing51 in the lower part 58 of the frame that supports shaft 26. A lever arm59 is fixed to the end of shaft 50 and is provided with means releasablysecuring it to frame part 58. A screw 60 that penetrates lever arm 59and is threaded into a tapped bore in frame part 58 is shown as a simpleand effective means for. coupling lever arm 59 to frame part 58 forrotating shaft 50 as the support frame is swung, removal of screw 60releasing the lever arm from the frame to permit independent rotation ofshaft 50 to its third position for purging. Preferably, an index detentis provided for indicating when shaft 50 is in its purge position. Asshown, the end of shaft 50 (see Fig. 7) opposite that to which theactuating assembly is mounted, is covered by a plate 5| that has acentral portion 62 projecting into the end of valve shaft bore 38 andadjacent the end surface of shaft 50. A spring biased index ball 63bears on the end surface of shaft 50 and engages a depression properlylocated in the shaft end to register with ball 63 when the shaft is inits purge position. An arrow 64 also may be applied to the exposed shaftend to indicate purge position.

I claim:

1. A hydraulic piston and cylinder assembly including structureenclosing a cylinder and mounting an output shaft that is rotatable byaxial movement of a piston in said cylinder, said housing structureenclosing also a cylindrical valve chamber disposed with its axisparallel to the axis of rotation of said output shaft, and a pair ofpassages each having an input reach opening outwardly through saidstructure for connection to one of a pair of supply lines, said passageshavin output reaches communicating with opposite ends of said cylinder,and each of said reaches entering said valve chamber through a port thatis spaced from each other port, a valve body rotatable in said chamberbetween a first position wherein a pair of passageways provided by saidbody respectively interconnect the input and output reaches of therespective passages and a second position wherein a passageway providedby said body interconnects said mounted on said support arm and movabletherewith into engagement with said worm gear by swinging of the supportarm to move said valve body to its said second position and movable outof engagement with said gear when the support arm is swung to move saidvalve body to its first said position, and means for rotating said worm.

2. A hydraulic piston and cylinder assembly including housing structureenclosing a cylinder and mounting an output shaft rotatable by axialmovement of a piston in said cylinder, said housing structure enclosinga cylindrical valve chamber disposed with its axis parallel to the axisof said output shaft and a pair of passages each having an input reachopening outwardly through said structure for connection to one of a pairof hydraulic lines, said passages having output reaches respectivelycommunicating with opposite ends of said cylinder, and each of saidreaches entering said valve chamber through a port that is spaced fromeach other port, a valve body rotatable in said chamber between a firstposition wherein a pair of passageways provided by said bodyrespectively interconnects the input and output reaches of saidpassages, a second position angularly spaced in one direction ofrotation from said first position and wherein a passageway provided bysaid body interconnects said output reaches and disconnects them fromsaid input reaches, and a third position angularly spaced in theopposite direction of rotation from said first position and wherein apassageway provided by said body interconnects said input .reaches anddisconnects them from said output reaches, a worm gear secured to saidoutput shaft, a support arm mounted on said structure for swingingabout'the axis of rotation of said valve body, a worm mounted on saidsupport arm and movable therewith into and out of engagement with saidworm gear by swinging of said shaft and valve body, releasable meansconnecting said supportarm to said valve body for moving the latter toits second said position when said arm is swung to engage said worm andworm gear, and means limiting swinging movement of the support arm tomove the worm away from the worm gear to limit movement of the valvebody in the corresponding direction and while connected to said arm tothe second said position of the valve body.

STANLEY A. JACQUES.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 584,500 Galloway June 15, 1897716,783 Sullivan Dec. 23, 1902 1,393,837 Schneider Oct. 18, 19211,477,557 Guenst Dec. 18, 1923 1,479,440 Abele Jan. 1, 1924 2,127,877Maglott Aug. 23, 1938 2,453,328 Lee Nov. 9, 1948

